Automobiles (also known as cars) are vehicles that use an internal combustion engine to propel the wheels. They usually have four wheels and can be powered by gasoline, diesel fuel, or other liquid petroleum products. The term “automobile” is also used to refer to the industry that manufactures them, including parts and accessories.
The automobile revolutionized twentieth-century society, becoming the backbone of a new consumer goods-oriented economy and one of the largest industrial employers. It was the chief customer of the steel and petroleum industries and the largest user of many other industrial goods, driving development of the ancillary industries that support it. By the 1920s, it ranked first in value of output and provided one out of six jobs in America.
Invented and perfected in Germany and France by such men as Gottlieb Daimler, Karl Benz, and Nicolaus Otto toward the end of the nineteenth century, it was only after World War I that mass production techniques made the automobile affordable for most Americans. Henry Ford introduced the Model T and William Durant founded General Motors, and they dominated the industry by the 1930s.
In the postwar era, engineering was subordinated to the questionable aesthetics of nonfunctional styling and quality deteriorated to such an extent that by the mid-1960s American-made cars were being delivered to retail buyers with an average of twenty-four defects per unit. At the same time, the higher per-unit profits that Detroit made on its gas-guzzling “road cruisers” came at a price in terms of increased air pollution and a drain on dwindling world oil reserves.
As the demand for automobiles increased, manufacturers produced ever more varieties and styles. In addition to the classic sedans, which have two doors, there are coupes, which are sportier and often more expensive; convertibles, which open with a roof that can be tilted up or down for greater versatility; and SUVs, which are derived from station wagons and can carry plenty of passengers and cargo.
A key feature of most modern automobiles is their drivetrain, a system that transfers power from the engine to the wheels. Most drivetrains are driven by a gasoline-powered engine, though diesel and electrical systems are also used.
The engines and drivetrains in modern automobiles are complex, with a number of mechanical components. Many engineers, chemists, and physicists are employed to develop, improve, and test them. The automotive industry also uses research and development engineers to design and produce new parts, chassis, bodywork, electronic equipment, control systems, service devices, and safety equipment. Research and development are crucial to the success of the automobile industry. It is estimated that the auto industry spent more than $170 billion on research and development in 2010. These investments have led to substantial improvements in the performance of automobiles, including improved mileage and fewer emissions. Many of these improvements have been achieved through the application of computer-aided design. Also known as CAD, this technology allows designers to create and test their ideas digitally before building physical prototypes.